The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 29, 2010
Filed:
Mar. 09, 2007
Applicant:
Paul Russell Dalluge, Marshalltown, IA (US);
Inventor:
Paul Russell Dalluge, Marshalltown, IA (US);
Assignee:
Fisher Controls International LLC, Marshalltown, IA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16K 51/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
Apparatus to vary the effective spring rate of diaphragm actuators are described. An example spring assembly for use in a diaphragm actuator includes a first spring operatively coupled to a diaphragm plate and an actuator stem, and a second spring operatively coupled to the actuator stem and configured to be serially operative with the first spring. Additionally, a movable spring seat is disposed between the first and second springs.